Serum
mIU/L
Age related ranges:
up to 6 days: 0.70 to 15.20 mIU/L
6 days up to 4 months: 0.72 to 11.00 mIU/L
4 months up to 1 year: 0.73 to 8.35 mIU/L
1 year up to 7 years: 0.70 to 5.97 mIU/L
7 years up to 12 years: 0.60 to 4.84 mIU/L
12 years up to 20 years: 0.51 to 4.30 mIU/L
20 years and above: 0.27 to 4.20 mIU/L
If TSH <0.35, Patient overtreated – reduce dose and retest after 4-6 weeks. This guidance is not applicable for pregnancy, thyroid cancer, or secondary hypothyroidism due to pituitary or hypothalamic disorders.
If TSH within normal range then acceptable if asymptomatic, repeat test annually. Symptomatic patients may benefit from reducing TSH below 1.0mU/L, but avoid suppressing TSH below the reference range. This guidance is not applicable for pregnancy, thyroid cancer, or secondary hypothyroidism due to pituitary or hypothalamic disorders.
If TSH >4.5 Patient Undertreated – if taking medication as prescribed, increase dose and retest in 4-6 weeks. This guidance is not applicable for pregnancy, thyroid cancer, or secondary hypothyroidism due to pituitary or hypothalamic disorders.
Local test
1 day
Can be added on to an existing request up to 4 days following sample receipt
25 days
Specimen Labelling Procedure